Generally, a dishwasher is an apparatus that sprays high-pressure wash water to dishes received therein to wash the dishes and dries the washed dishes. Specifically, the dishwasher is operated such that high-pressure wash water is sprayed into a tub, in which dishes are received, and the sprayed wash water removes foreign matter, such as food waste, from the surfaces of the dishes.
The dishwasher is configured such that food waste contained in wash water is filtered by a filter for reuse of the used wash water and such that wash water containing detergent is supplied to smoothly separate food waste from dishes. In recent years, a dishwasher that increases the temperature of wash water or generates steam using a heater to improve washing efficiency has been widely used.
A conventional dishwasher includes a case defining the external appearance thereof, a washing tub provided in the case for defining a washing space in which dishes are washed, a door disposed in front of the washing tub for opening and closing the washing tub, a drive unit provided under the washing tub for supplying, collecting, circulating, and draining wash water, lower, upper, and top spraying units for spraying wash water supplied by the drive unit to the dishes, and lower, upper, and top racks separably provided between the lower, upper, and top spraying units, the lower, upper, and top racks being selectively loaded in the washing tub based on the kind or size of the dishes.
Each rack is provided at the lower part thereof with a plurality of moving rollers, which are guided along guide rails provided at the inside of the washing tub such that the rack is introduced into or withdrawn from the washing tub.
The lower rack is disposed adjacent to the lower spraying unit to receive relatively large-sized dishes. The upper rack is disposed adjacent to the upper spraying unit to receive relatively small-sized dishes. The top rack is disposed adjacent to the top spraying unit to receive eating utensils (e.g. spoons and knives) and cooking utensils (e.g. dippers and whisks) having smaller sizes than dishes.
In order to wash dishes using the dishwasher, a user opens the door of the dishwasher, withdraws one of the racks from the washing tub, places dishes in the withdrawn rack, pushes the withdrawn rack back into the washing tub of the dishwasher, and closes the door.
Subsequently, when the user operates the dishwasher, wash water is individually or simultaneously supplied to the lower, upper, and top spraying units according to the operation of the drive unit in order to wash the dishes loaded in the lower, upper, and top racks.
The eating utensils and the cooking utensils, which are loaded in the top rack, are individually withdrawn and arranged after washing is completed. The sizes of the eating utensils and the cooking utensils, which are loaded in the top rack, are relatively small. In particular, each of the eating utensils and the cooking utensils has a predetermined length. When washing is completed, therefore, the eating utensils and the cooking utensils are individually withdrawn from the top rack, which is troublesome.